TFT-LCDs (Thin Film Transistor-Liquid Crystal Displays) are widely used in the field of flat panel display because of their low radiation, thinness and low power consumption etc. Most of the desktop TFT-LCDs are based on the TN (Twisted Nematic) mode, however, two electrodes of TN-type liquid crystal displays are respectively formed on the upper and lower substrates, and the liquid crystal molecules rotate in a plane orthogonal to the substrates. Due to the optical anisotropy of liquid crystal molecules, the optical path lengths of the light entering the human eyes after passing by the liquid crystal molecules from different angles are different; this inevitably leads to the viewing angle problem.
In order to solve the viewing angle problem, the TN type LCDs are commonly added a viewing angle compensation film thereon when they are personally used or used in office environments where high requirement of viewing angle is not asked for. While, requirements of viewing angles for television and handheld PDA (Personal Digital Assistant) products are higher, several new LCD display models, such as the FFS (Fringe Field Switching) mode, IPS (In-Plane Switching) mode are applied to the related products. FIG. 1 discloses a cross-sectional structure of an existing FFS type LCD. As shown in FIG. 1, both of the first electrode 81 and the second electrode 82 of the FFS type LCD 800 are formed on the bottom substrate and disposed on different layers; and in the pixel areas, the first electrode 81 is configured as an entire plane but the second electrode 82 is configured in strips. FIG. 2 discloses a cross-sectional structure of an existing IPS type LCD. As shown in FIG. 2, both of the first electrode 91 and the second electrode 92 of the IPS type LCD 900 are formed on the bottom substrate and disposed on the same layer; and in the pixel areas, the first electrode 91 and the second electrode 92 are configured by interlaced strips. Since in the FFS type LCD 800 and the IPS type LCD 900, the first electrodes 81, 91 and the second electrodes 82, 92 are formed on the same substrate, the liquid crystal molecules rotate in a plane parallel to the substrate, and thus the viewing angle characteristics can be improved to achieve a wide viewing angle display.
For the TN type LCDs added with a viewing angle compensation film with low technical threshold, they are widely used. However, because the compensation film is fixed, it cannot be realized to compensate for arbitrary gray scale at any angle. Therefore, the inherent gray scale inversion phenomenon in the TN type LCDs still remains. For the FFS type and IPS type LCDs with high technical threshold, they are monopolized by patent owners with high royalties.
Therefore, it is necessary to provide improved technical solutions to overcome the above technical problems in the existing technology.